Modern assembly line manufacturing processes are typically highly automated to manipulate materials and devices and create a finished product. Quality control and maintenance processes often rely on human skill, knowledge and expertise for inspection of the manufactured product and manufacturing process.
Typical assembly line processes for processing wafers (e.g., semiconductor devices or materials) employ no specific inspection techniques at a robotic arm for alignment with a wafer carrying pod, also termed as a wafer pod, aside from manual inspections. Examples of wafer pods include standard mechanical interface (SMIF) pods which may hold a plurality of wafers, or front opening unified pods (FOUPs) which may hold larger wafers.
Alignment is important as a robotic arm that is not aligned with a wafer pod may place or retrieve wafers from the wafer pod in a manner that damages the wafer. For example, a non-aligned robotic arm may damage a wafer by impacting the wafer carried by the non-aligned robotic arm against a side, front, or rear wall of the wafer pod. However, conventional manual inspection and alignment techniques require large amounts of overhead and expensive hardware, but still fail to produce satisfactory results. Therefore, conventional inspection techniques are not entirely satisfactory.